$(document).ready(function(){
	var checkboxes = $("#productAttributes").find("input[type='checkbox']").get();
	$("div#cartAdd input[type='image']").click(function() {
		var i = 0
		if (checkboxes.length != 0) {
			$.each(checkboxes, function() {	if(this.checked) {i++} });
			if(i==0) {alert("You must select at least one custom color.");return false;};
	}
  });
});